This screenshot shows the option screen that is displayed when you open a rule set layout and no fields have been selected for it. In this screen you must choose to either select the fields you want to include in the layout, or choose to apply one of the existing form templates, if any, to the layout.

The options screen in this image contains one option: Select fields to display. If the rule set already had some form templates defined, they would be displayed as options on this screen.